A Comparative Analysis of Embryo and Endosperm Proteome from Seeds of Jatropha curcas

Jatropha curcas is an important economic plant for biodiesel, which is extracted mainly from the endosperm of its mature seeds. Despite the morphological and functional differences between the embryo and endosperm, proteomic characteristics of the two tissues are not yet known. Similar proteomic profiles were observed in the two-dimensional gel electrophoresis maps from the two tissues. There were 380 and 533 major protein spots in the embryo and endosperm, respectively. Fourteen identical spots, showing a notable change, were selected and identified by tandem mass spectrometry. Among these proteins, dihydrolipoamide acetyltransferase （spot 27） participates in tricarboxylic acid cycle, which is an amphibolic pathway. The two parts both included proteins related to stress （spots 8, 115, 118, 125, 130） and signal transduction （spots 7, 100, 108）. According to the volume percentage of proteins in embryo and endosperm, the proteins in endosperm （spots 54, 61, 73） were catabolism-related enzymes and reserves to provide the nutrition for seed germination; the proteins in embryo （spots 27, 62, 122） were inclined to anabolism and utilized the nutrition from the endosperm to generate a new life.     

A Comparative Analysis of Embryo and Endosperm Proteome from Seeds of Jatropha curcas

Jatropha curcas is an important economic plant for biodiesel, which is extracted mainly from the endosperm of its mature seeds. Despite the morphological and functional differences between the embryo and endosperm, proteomic characteristics of the two tissues are not yet known. Similar proteomic profiles were observed in the two-dimensional gel electrophoresis maps from the two tissues. There were 380 and 533 major protein spots in the embryo and endosperm, respectively. Fourteen identical spots, showing a notable change, were selected and identified by tandem mass spectrometry. Among these proteins, dihydrolipoamide acetyltransferase (spot 27) participates in tricarboxylic acid cycle, which is an amphibolic pathway. The two parts both included proteins related to stress (spots 8, 115, 118, 125, 130) and signal transduction (spots 7, 100, 108). According to the volume percentage of proteins in embryo and endosperm, the proteins in endosperm (spots 54, 61, 73) were catabolism-related enzymes and reserves to provide the nutrition for seed germination; the proteins in embryo (spots 27, 62, 122) were inclined to anabolism and utilized the nutrition from the endosperm to generate a new life.     

麻疯树核糖体失活蛋白基因的克隆和表达

麻疯树(Jatropha curcas L.)核糖体失活蛋白(curcin)是存在于麻疯树种子中的一种毒性较强的蛋白,它与蓖麻毒蛋白和相思子毒蛋白的性质相似,属Ⅰ型核糖体失活蛋白.从麻疯树种子中分离得到一种分子量为28.2 kD的蛋白质,其对无细胞系统中蛋白质合成的抑制活性较强,IC50为(0.19±0.01)nmol/L,具有RNA N-糖苷酶活性.依据curcin的N端部分氨基酸设计简并引物,通过RT-PCR和5'-RACE技术从未成熟种子总RNA中克隆到curcin全长cDNA序列.该cDNA全长由1 173个碱基组成,包含一个编码293个氨基酸的前体蛋白,前42个氨基酸为信号肽.推测的多肽序列与测定的蛋白质N端序列相同,与多种己发表的Ⅰ型核糖体失活蛋白和Ⅱ型核糖体失活蛋白的A链有一定的同源性.将curcin的编码区与表达载体pQE-30相连后,转入大肠杆菌(Escherichia coil)M15菌株中得到了有效的表达.将表达的融合蛋白纯化后发现,它具有抑制无细胞系统蛋白质合成的能力.     

麻疯树核糖体失活蛋白基因的克隆和表达

麻疯树(Jatropha curcas L.)核糖体失活蛋白(curcin)是存在于麻疯树种子中的一种毒性较强的蛋白,它与蓖麻毒蛋白和相思子毒蛋白的性质相似,属Ⅰ型核糖体失活蛋白。从麻疯树种子中分离得到一种分子量为28.2kD的蛋白质,其对无细胞系统中蛋白质合成的抑制活性较强,IC_(50)为(0.19±0.01)nmol/L,具有RNA N-糖苷酶活性。依据curcin的N端部分氨基酸设计简并引物,通过RT-PCR和5′-RACE技术从未成熟种子总RNA中克隆到curcin全长cDNA序列。该cDNA全长由1 173个碱基组成,包含一个编码293个氨基酸的前体蛋白,前42个氨基酸为信号肽。推测的多肽序列与测定的蛋白质N端序列相同,与多种已发表的Ⅰ型核糖体失活蛋白和Ⅱ型核糖体失活蛋白的A链有一定的同源性。将curcin的编码区与表达载体pQE-30相连后,转入大肠杆菌(Escherichia coil)M15菌株中得到了有效的表达。将表达的融合蛋白纯化后发现,它具有抑制无细胞系统蛋白质合成的能力。     

Characterization of a New Stearoyl-acyl Carrier Protein Desaturase Gene from Jatropha curcas

A new full-length cDNA of stearoyl-acyl carrier protein desaturase was obtained by RT-PCR and RACE techniques from developing seeds of Jatropha curcas. Sequence alignment showed that its deduced amino acid sequence had high similarity with other stearoyl-acyl carrier protein desaturases. The gene was functionally expressed in E. coli and the desaturating activity of recombinant protein was easily detected when assayed in vitro with added spinach ferredoxin. Southern blot analysis indicated that the gene was a member of a small gene family. Northern blot analysis revealed it was highly expressed in developing fruits of J. curcas. Revisions requested 16 December 2005; Revisions received 6 February 2006     

Chemical Constituents from Roots of Jatropha curcas

Thirteen compounds were isolated from the roots of datropha curcas L. Combining the determination of physico-chemical constants and spectral analyses (IR, 1H-NMR, 13C-NMR, EIMS, FABMS), the structures of the compounds were identified as 5α-stigmastane-3, 6-dione (1), nobiletin (2), β-sitosterol (3), taraxerol (4), 2S-tetracosanoic acid glyceride-1(5),5-hydroxy-6,7-dimethoxycoumarin (6), jatropholone A (7), jatropholone B (8), 6-methoxy-7-hydroxycoumarin (9), caniojane (10), 3-hydroxy-4-methoxybenzaldehyde (11), 3-methoxy-4-hydroxybenzoic acid (12) and daucosterol (13). Among them, compound 5 is a new compound which has never been reported in China and abroad, compound 1, 2, 9, 10, 11, 12 were first time isolated from the plant, 7 and 8 are a pair of stereoisomers which can be inverted in dilute basic solution. 10 is a diterpenoid containing peroxide bridge.     

The Diterpenoids from Jatropha curcas L.

Three diterpenoids have been isolated from the roots of Jatropha curcas L. They are identified as tetracyclic aromatic diterpenoids jatropholone A, jatropholone B and new diterpenoidnamed jatrophol. The structure of the new diterpenoid was elucidated as 16-hydroxyjatropholone by spectral analysis (UV, IR, MS, 1HNMR, 13CNMR). A coumarino-lignan jatrophin,a coumarin tomentin, β-D-glycoside-β-sitosterol, taraxerol and β-sitosterol have been isolatedalso.     

红桂木凝集素的纯化与性质研究

红桂木（Ａｒｔｏｃａｒｐｕｓｌｉｎｇｎａｎｅｎｓｉｓ）、俗名胭脂,属桑科桂木属,为亚热带、热带植物．红桂木种子含丰富的红桂木凝集素（Ａｒｔｏｃａｒｐｕｓｌｉｎｇｎａｎｅｎｓｉｓｌｅｃｔｉｎ,ＡＬＬ）,但迄今国内外均未见关于它的报道．我们采用Ｇａｌ－Ｓ...     

鹰嘴豆种子胰蛋白酶抑制剂的分离纯化与鉴定

为了寻找具有药物作用的天然胰蛋白酶抑制物,采用硫酸铵分级沉淀、离子交换层析(DEAE-纤维素52)及Sephadex G-100凝胶层析等方法, 从鹰嘴豆种子中分离出一种鹰嘴豆胰蛋白酶抑制剂（CPTI）. 研究表明：CPTI对胰蛋白酶有较强的抑制作用,抑制率达80%,而对胰凝乳蛋白酶抑制作用较弱,抑制率为32%, 对胃蛋白酶、木瓜蛋白酶及枯草杆菌蛋白酶均无抑制作用; 用SDS-PAGE测得CPTI近似分子质量为25.7 kD; CPTI具有较高的热稳定性,在100 ℃下加热60 min,对胰蛋白酶活性仍保持78%抑制率; Lineveaer-Burk作图得知该抑制剂属竞争性抑制类型. 动力学测定显示,来自鹰嘴豆中的CPTI对胰蛋白酶的抑制作用常数(Ki)为3.99×10^-7 mol/L.     

从麻疯树上胚轴外植体再生植株

以麻疯树上胚轴为实验材料在MS添加IBA和BA的培养基上进行离体培养实验.结果表明,在IBA O.1 mg/L与BA 0.2～0.7 mg/L组合的条件下,不定芽从上胚轴外植体的表面直接被诱导分化,其中以在MS IBA 0.1 mg/L BA 0.5 mg/L上的诱导率最高.从愈伤组织来源的植株再生需要IBA 0.5 mg/L与BA 0.1 mg/L、IBA 0.5 mg/L与BA0.2mg/L以及IBA1.0mg/L与BA0.5mg/L的激素组合,其分化的最佳培养基是MS IBA1.0 mg/L BA0.5 mg/L.生长健壮的不定芽和再生植株能在无激素的MS基本培养基上生根.发育良好的再生苗可成功地转移到温室栽培而没有可见的变异.     

Purification and Characterization of the Acidic Lectin from Winged Bean Seeds

Winged bean acidic lectin was purified by DEAE-Sephadex A-50 and affinity chromatography on N-acetylgalactosamine-agarose gel. The purified lectin was a glycoprotein homogeneous on polyacrylamide gel electrophoresis, isoelectric focusing, and gel filtration. The molecular weight of the lectin was 52,000 by gel filtration, and SDS-polyacrylamide gel electrophoresis gave a single component of molecular weight of 27,000. Its isoelectric point was 5.5. The acidic lectin was rich in acidic amino acids, and contained 2mol of methionine but no cystine. It also agglutinated both trypsinized and untreated human erythrocytes (types A, B, AB and O), but not rabbit erythrocytes. The hemagglutination was inhibited by d-galactose and related sugars. Modification of the acidic lectin with N-bromosuccinimide caused a concomitant loss of the hemagglutinating activity with oxidation of tryptophan residue. The acidic lectin was immunologically different from the purified winged bean basic lectin by double immunodiffusion using antiserum raised against the basic lectin.     

麻疯树叶中过氧化物酶JCP-1的分离纯化和几种特性的检测

麻疯树叶片蛋白粗提液经硫酸铵分级沉淀,强阴离子琼脂糖、强阳离子琼脂糖和交联葡聚糖层析,得到一个比活为4499U·mg-1（蛋白）过氧化物酶,命名为JCP-1。其分子量为49kDa,等电点为pH3.3,最适pH为5.0-6.0。以H2O2为底物的Km为2.14mmol·L-1。JCP-1具有宽泛的最适保存pH（7.0-11.0）和较高的耐热性（80℃高温处理15min,活性保持在90%以上）。30%PEG6000处理模拟干旱胁迫及50℃高温胁迫麻疯树苗,其叶片中JCP-1活性分别提高121%和155%。     

Purification and Characterization of a Lectin from Crotalaria paulina Seeds

A lectin was purified from Crotalaria paulina seeds by ion-exchange and FPLC molecular exclusion chromatography. CrpL had an apparent molecular mass of 30 kDa, as determined by SDS-PAGE under non-reducing and reducing conditions. CrpL effectively agglutinated human and cow erythrocytes, and this activity was not affected by 20 mM EDTA, showing no dependence of divalent cations. Hemagglutination was inhibited by N-acetyl- D-galactosamine, D-galactose and was also inhibited by glycoproteins, fetuin and asialofetuin. The N-terminal amino acid sequence of CrpL was identical to those of other lectins from the genus Crotalaria, and amino acid composition showed high amounts of Asx and Glx, and was rich in Gly, Ala and Ser, as also reported for lectins from other Crotalaria species. CrpL inhibited the growth of Xanthomonas axonopodis pv. phaseoli and Xanthomonas axonopodis pv. passiflorae, suggesting a role of this lectin in the defense of seeds against bacterial infections.     

Purification and Characterization of Lectin from Seeds of Delonix regia

A lectin from the crude extract of seeds of Delonix regia (DRL) has been purified by ammonium sulphate fractionation followed by specific adsorption on Sephadex G-50 column and subsequent displacement with 100 mM D-glucose. The purified lectin (yield 1.41 mg g^?1 dry seed) is a hetero-tetramer of 156 kD in size, consisting of four polypeptides (M_r of 32, 36, 42 and 46 kD) as detected on SDS-PAGE. It is a thermostable protein and remains active between pH 2.0–11.0. The lectin agglutinated erythrocytes of human and other primates. The hemagglutinating activity was not affected by cations and chelating agents. Of the 23 different sugars tested for specificity, maximum inhibition of the hemagglutination was shown by D-glucose. The immunological crossreactions of DRL with monospecific antibodies against SBA, Con A, PNA, DBA and PHA-E indicate that DRL is very closely related to Concanavalin A.     

天然食用红木色素的分离纯化与结构表征

本文采用萃取法和重结晶法对红木种子中的红木色素进行了分离和纯化,利用分光光度法对油溶性的红木素产品进行了定量分析,并借助UV、FUR、MS、^1HNMR及^13CNMR等测试手段对红木素的组成和结构进行了表征。     

白桂木凝集素的纯化与性质的研究

白桂木种子粉经抽提、３０～６０％饱和度硫酸铵沉淀和亲和层析,已获得纯化的白桂木凝集素（Ａｒｔｏｃａｒｐｕｓｈｙｐａｒｇｙｒｂｕｓｌｅｃｔｉｎ）。浓度梯度ＰＡＧＥ,显示基本是均一的蛋白质带,分析表明,它是由分子量为１５０００和１９０００两种亚基组成,Ｎ端为精氨酸和丙氨酸,ｐＩ９．１０、８．４５、８．１０,中性精含量约６．９％,氨基糖约０．４％,能凝集多种动物红细胞和人Ａ、Ｂ、Ｏ和ＡＢ血型红细胞,凝集活力受Ｇａ１ＮＡｃ、Ｇａｌ和棉子糖的抑制,对热较敏感,在ｐＨ４．５～９．５的范围内．ｐＨ的改变不影响它的血凝活力。     

Morphogenesis and plant regeneration from tissue cultures of Jatropha curcas

Techniques for the regeneration of Jatropha curcas L. from various explants have been developed. Regeneration from hypocotyl, petiole and leaf explants was evaluated on a range of concentrations of zeatin, kinetin and N⁶ benzyladenine (BA) either singly or in combination with indole-3-butyric acid (IBA). Higher regeneration from hypocotyl and petiole explants was obtained on BA with IBA than on zeatin- or kinetin-supplemented media. Leaf discs from the third expanding leaf exhibited higher regeneration potential than those from the fourth leaf. Independent of the explant type, direct adventitious shoot bud induction was recorded highest on MS medium with 2.22 M BA and 4.9 M IBA. Although the same BA concentration but with reduced IBA concentration (0.49 M) proved effective in callus mediated regeneration from hypocotyl and leaf explants, the petioles required lower concentrations of the two growth regulators (0.44 M BA and 0.49 M IBA). Regenerated shoots could be rooted on growth regulator-free gelled full-strength MS medium. Following simple hardening procedures, the in vitro-raised plants could be transferred to soil and grown to maturity in the field.Abbreviations BA N⁶ benzyladenine - IAA indole-3-acetic acid - IBA indole-3-butyric acid - MS Murashige & Skoog's (1962) medium - NAA -naphthaleneacetic acid     

小桐子提取物除草活性的生物测定

为全面了解小桐子(Jatropha curcas L. )提取物的除草活性,以萝卜(Raphanus sativus L. )、苋(Amaranthus tricolor L. )、苏丹草[Sorghum sudanense (Piper) Stapf]和黑麦草(Lolium perenne L. )为实验材料,对小桐子果壳和枝叶的水、乙醇(体积分数95%)、正丁醇、乙酸乙酯、氯仿和石油醚粗提物的除草活性进行了生物测定,并从中筛选出抑制作用最强的水粗提物进行进一步的活性组分分离及其除草活性的生物测定.测定结果显示,小桐子果壳和枝叶的6种溶剂提取物(10 g·L~(-1))对供试的4种植物幼苗的根长和茎高均有不同程度的抑制作用,其中水粗提物和乙醇(体积分数95%)粗提物的抑制作用较强,且水粗提物对供试的4种植物幼苗的根长和茎高的抑制作用均在75%以上,显著高于其他溶剂粗提物(P<0.05);石油醚粗提物的抑制作用最小,均在10%以下.小桐子果壳和枝叶水粗提物的石油醚、氯仿、乙酸乙酯、正丁醇和水萃取物(10 g·L~(-1))对萝卜和苏丹草幼苗的根长和茎高均有不同程度的抑制作用,其中水、正丁醇和乙酸乙酯萃取物的抑制作用显著高于氯仿和石油醚萃取物,抑制率均在70%以上;水萃取物的抑制作用最强,抑制率均在80%以上;石油醚萃取物的抑制作用最小,抑制率均在10%以下.研究结果表明,小桐子果壳和枝叶的水粗提物具有一定的除草活性,其有效成分为极性较大的组分.     

麻风树LEC1基因的生物信息学分析

LEC1是调控植物种子发育过程和油脂产量的重要基因。本文选择功能已知的拟南芥LEC1基因为参考序列,对麻风树LEC1基因开展了蛋白组分和理化性质分析,蛋白结构和功能预测,系统进化分析等生物信息学研究,为进一步研究麻风树LEC1基因的生物学功能奠定了基础。